### Please describe the problem.

I have what I speculate is an interoperability problem with two git-annex versions: on one end, it's trying to run `true` over SSH and on the other end `git-annex-shell` is saying that's not a valid command.

I have a rather gnarly git-remote-gcrypt setup (is there one that isn't?) with a gcrypt remote for the git history and annex content. I honestly barely remember how I set this up, and I'm constantly battling to remember how it works (not great, I know), but here are the notes I have so far:

https://anarc.at/services/backup/#encrypted-remotes

Obviously, I have tried to follow the [[tips/fully_encrypted_git_repositories_with_gcrypt/]] tutorial, but I might have drifted off at some point. I often get confused between the builtin [[encryption]] features and the [[special_remotes/gcrypt]] special remote.

### What steps will reproduce the problem?

I think the trick is to setup a remote gcrypt repo with a hardcoded `command="GIT_ANNEX_SHELL_APPENDONLY=true git-annex-shell -c \"$SSH_ORIGINAL_COMMAND\""` entry in `authorized_keys`. If I drop the `command` parameter from the line, the command goes through fine.

### What version of git-annex are you using? On what operating system?

The "client" end is 8.20210223-2 on Debian bullseye, the remote is 7.20190129-3 on Debian buster.

### Please provide any additional information below.

 I suspect that something was introduced after the buster release that runs this extra command on start:

    ssh remote true

Which SSH turns into:

    ssh remote git-annex-shell -c true

Even with a non-restricted SSH key, the above fails with:

    fatal: unrecognized command 'true'
    git-annex-shell: git-shell failed

... which is, for me, the smoking gun here.

[[!format sh """
# If you can, paste a complete transcript of the problem occurring here.
# If the problem is with the git-annex assistant, paste in .git/annex/daemon.log

anarcat@curie:maison(master)$ LANG=C.UTF-8 git annex sync --content -J2  --debug
[2021-08-19 10:39:04.710287879] process [2036863] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","git-annex"]
[2021-08-19 10:39:04.71270528] process [2036863] done ExitSuccess
[2021-08-19 10:39:04.713060458] process [2036864] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","--hash","refs/heads/git-annex"]
[2021-08-19 10:39:04.715240868] process [2036864] done ExitSuccess
[2021-08-19 10:39:04.71580494] process [2036865] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","log","refs/heads/git-annex..0134b426eaca4932d9bcc381bcb2c62609563651","--pretty=%H","-n1"]
[2021-08-19 10:39:04.71856682] process [2036865] done ExitSuccess
[2021-08-19 10:39:04.719607238] process [2036868] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch"]
[2021-08-19 10:39:04.720334517] process [2036869] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch-check=%(objectname) %(objecttype) %(objectsize)"]
[2021-08-19 10:39:04.738790271] process [2036872] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","commit","-a","-m","git-annex in anarcat@curie:/srv/video/maison"]
On branch master
nothing to commit, working tree clean
[2021-08-19 10:39:04.770958097] process [2036872] done ExitFailure 1
[2021-08-19 10:39:04.771335463] process [2036893] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","symbolic-ref","-q","HEAD"]
commit ok
[2021-08-19 10:39:04.773190824] process [2036893] done ExitSuccess
[2021-08-19 10:39:04.773504032] process [2036895] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","refs/heads/master"]
[2021-08-19 10:39:04.775743665] process [2036895] done ExitSuccess
[2021-08-19 10:39:04.776052102] process [2036896] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","--verify","-q","refs/heads/synced/master"]
[2021-08-19 10:39:04.777934271] process [2036896] done ExitSuccess
[2021-08-19 10:39:04.778257724] process [2036897] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","log","refs/heads/master..refs/heads/synced/master","--pretty=%H","-n1"]
[2021-08-19 10:39:04.781046264] process [2036897] done ExitSuccess
[2021-08-19 10:39:04.781665586] process [2036898] read: ssh ["-o","BatchMode=true","-S",".git/annex/ssh/anarc.at","-o","ControlMaster=auto","-o","ControlPersist=yes","-n","-T","anarc.at","true"]
[2021-08-19 10:39:05.937301502] process [2036898] done ExitSuccess
[2021-08-19 10:39:05.938577543] process [2036926] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","fetch","origin"]
[2021-08-19 10:39:06.108005272] process [2036926] done ExitSuccess
[2021-08-19 10:39:06.108743728] process [2036944] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","branch","-f","synced/master","refs/heads/master"]
[2021-08-19 10:39:06.113172855] process [2036944] done ExitSuccess
[2021-08-19 10:39:06.113913765] process [2036945] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","--verify","-q","refs/remotes/origin/master"]
[2021-08-19 10:39:06.118235086] process [2036945] done ExitSuccess
[2021-08-19 10:39:06.118916295] process [2036946] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","log","refs/heads/master..refs/remotes/origin/master","--pretty=%H","-n1"]
[2021-08-19 10:39:06.124140634] process [2036946] done ExitSuccess
[2021-08-19 10:39:06.124791141] process [2036947] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","--verify","-q","refs/remotes/origin/synced/master"]
[2021-08-19 10:39:06.128491407] process [2036947] done ExitSuccess
[2021-08-19 10:39:06.129062268] process [2036948] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","log","refs/heads/synced/master..refs/remotes/origin/synced/master","--pretty=%H","-n1"]
[2021-08-19 10:39:06.134308196] process [2036948] done ExitSuccess
pull origin ok
[2021-08-19 10:39:06.135431262] process [2036949] read: ssh ["-o","BatchMode=true","-S",".git/annex/ssh/anarcat@remote-annex","-o","ControlMaster=auto","-o","ControlPersist=yes","-n","-T","anarcat@remote-annex","true"]
[2021-08-19 10:39:06.5226911] process [2036949] done ExitFailure 1
[2021-08-19 10:39:06.524455991] process [2036956] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","fetch","offsite-git"]
git-annex-shell: git-shell failed
rsync: connection unexpectedly closed (0 bytes received so far) [Receiver]
rsync error: error in rsync protocol data stream (code 12) at io.c(228) [Receiver=3.2.3]
gcrypt: Repository not found: rsync://anarcat@remote-annex:/home/anarcat/offsite/Videos.git/
gcrypt: ..but repository ID is set. Aborting.
[2021-08-19 10:39:07.057455548] process [2036956] done ExitFailure 128
pull offsite-git ok
[2021-08-19 10:39:07.058197157] process [2037001] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","git-annex"]
[2021-08-19 10:39:07.063254024] process [2037001] done ExitSuccess
[2021-08-19 10:39:07.064018134] process [2037002] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","--hash","refs/heads/git-annex"]
[2021-08-19 10:39:07.069653083] process [2037002] done ExitSuccess
[2021-08-19 10:39:07.07062786] process [2037003] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","log","refs/heads/git-annex..0134b426eaca4932d9bcc381bcb2c62609563651","--pretty=%H","-n1"]
[2021-08-19 10:39:07.076284072] process [2037003] done ExitSuccess
[2021-08-19 10:39:07.077172323] process [2037004] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","ls-files","--stage","-z","--"]
[2021-08-19 10:39:07.078079618] process [2037005] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch-check=%(objectname) %(objecttype) %(objectsize)","--buffer"]
[2021-08-19 10:39:07.078694043] process [2037006] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch=%(objectname) %(objecttype) %(objectsize)","--buffer"]
[2021-08-19 10:39:07.079965189] process [2037007] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch=%(objectname) %(objecttype) %(objectsize)","--buffer"]
[2021-08-19 10:39:07.103420306] process [2037009] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch"]
[2021-08-19 10:39:07.107225054] process [2037010] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch-check=%(objectname) %(objecttype) %(objectsize)"]
[2021-08-19 10:39:07.108049882] process [2037011] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","check-attr","-z","--stdin","annex.backend","annex.largefiles","annex.numcopies","annex.mincopies","--"]
[2021-08-19 10:39:07.110542203] process [2037012] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","check-attr","-z","--stdin","annex.backend","annex.largefiles","annex.numcopies","annex.mincopies","--"]
[2021-08-19 10:39:07.365098056] process [2037013] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch"]
[2021-08-19 10:39:07.365245774] process [2037011] done ExitSuccess
[2021-08-19 10:39:07.365363864] process [2037014] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch"]
[2021-08-19 10:39:07.36572593] process [2037015] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch-check=%(objectname) %(objecttype) %(objectsize)"]
[2021-08-19 10:39:07.36730392] process [2037012] done ExitSuccess
[2021-08-19 10:39:07.367432763] process [2037016] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","check-attr","-z","--stdin","annex.backend","annex.largefiles","annex.numcopies","annex.mincopies","--"]
[2021-08-19 10:39:07.367787144] process [2037007] done ExitSuccess
[2021-08-19 10:39:07.367891318] process [2037017] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch-check=%(objectname) %(objecttype) %(objectsize)"]
[2021-08-19 10:39:07.368118899] process [2037006] done ExitSuccess
[2021-08-19 10:39:07.368213522] process [2037005] done ExitSuccess
[2021-08-19 10:39:07.368287754] process [2037004] done ExitSuccess
[2021-08-19 10:39:07.369558345] process [2037018] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","check-attr","-z","--stdin","annex.backend","annex.largefiles","annex.numcopies","annex.mincopies","--"]
[2021-08-19 10:39:07.370572764] process [2037019] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch"]
[2021-08-19 10:39:07.371432055] process [2037020] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch-check=%(objectname) %(objecttype) %(objectsize)"]
[2021-08-19 10:39:07.374759264] process [2037021] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch"]
[2021-08-19 10:39:07.375304372] process [2037022] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch-check=%(objectname) %(objecttype) %(objectsize)"]
[2021-08-19 10:39:07.378100534] process [2037023] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","branch","-f","synced/master","refs/heads/master"]
[2021-08-19 10:39:07.380269305] process [2037023] done ExitSuccess
[2021-08-19 10:39:07.380584318] process [2037024] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","symbolic-ref","-q","HEAD"]
[2021-08-19 10:39:07.38084529] process [2037025] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","symbolic-ref","-q","HEAD"]
[2021-08-19 10:39:07.383152906] process [2037025] done ExitSuccess
[2021-08-19 10:39:07.383152909] process [2037024] done ExitSuccess
[2021-08-19 10:39:07.383556344] process [2037026] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","refs/heads/master"]
[2021-08-19 10:39:07.38382986] process [2037027] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","refs/heads/master"]
[2021-08-19 10:39:07.385869655] process [2037026] done ExitSuccess
[2021-08-19 10:39:07.385998224] process [2037027] done ExitSuccess
[2021-08-19 10:39:07.386579545] process [2037028] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","--verify","-q","refs/remotes/origin/synced/master"]
[2021-08-19 10:39:07.386748615] process [2037029] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","--verify","-q","refs/remotes/offsite-git/synced/master"]
[2021-08-19 10:39:07.388481211] process [2037028] done ExitSuccess
[2021-08-19 10:39:07.388627634] process [2037029] done ExitSuccess
[2021-08-19 10:39:07.389087617] process [2037030] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","log","refs/remotes/origin/synced/master..refs/heads/synced/master","--pretty=%H","-n1"]
[2021-08-19 10:39:07.389447787] process [2037031] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","log","refs/remotes/offsite-git/synced/master..refs/heads/synced/master","--pretty=%H","-n1"]
[2021-08-19 10:39:07.391475061] process [2037030] done ExitSuccess
[2021-08-19 10:39:07.391885609] process [2037032] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","--verify","-q","refs/remotes/origin/git-annex"]
[2021-08-19 10:39:07.392072048] process [2037031] done ExitSuccess
[2021-08-19 10:39:07.392422194] process [2037033] call: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","--verify","-q","refs/remotes/offsite-git/git-annex"]
[2021-08-19 10:39:07.393853689] process [2037032] done ExitSuccess
[2021-08-19 10:39:07.394223125] process [2037034] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","log","refs/remotes/origin/git-annex..git-annex","--pretty=%H","-n1"]
[2021-08-19 10:39:07.394252126] process [2037033] done ExitSuccess
[2021-08-19 10:39:07.394616572] process [2037035] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","log","refs/remotes/offsite-git/git-annex..git-annex","--pretty=%H","-n1"]
[2021-08-19 10:39:07.396719833] process [2037034] done ExitSuccess
[2021-08-19 10:39:07.396989352] process [2037035] done ExitSuccess
[2021-08-19 10:39:07.397288729] process [2037019] done ExitSuccess
[2021-08-19 10:39:07.397649558] process [2037020] done ExitSuccess
[2021-08-19 10:39:07.397943289] process [2037021] done ExitSuccess
[2021-08-19 10:39:07.398193463] process [2037022] done ExitSuccess
[2021-08-19 10:39:07.398430683] process [2037018] done ExitSuccess
[2021-08-19 10:39:07.398671489] process [2037016] done ExitSuccess
[2021-08-19 10:39:07.399335705] process [2037036] read: ssh ["-O","stop","-S","anarcat@remote-annex","-o","ControlMaster=auto","-o","ControlPersist=yes","localhost"]
[2021-08-19 10:39:07.405590596] process [2037036] done ExitSuccess
[2021-08-19 10:39:07.406058089] process [2037037] read: ssh ["-O","stop","-S","anarc.at","-o","ControlMaster=auto","-o","ControlPersist=yes","localhost"]
[2021-08-19 10:39:07.412095481] process [2037037] done ExitSuccess

# End of transcript or log.
"""]]

Key part above:

    [2021-08-19 10:39:06.135431262] process [2036949] read: ssh ["-o","BatchMode=true","-S",".git/annex/ssh/anarcat@remote-annex","-o","ControlMaster=auto","-o","ControlPersist=yes","-n","-T","anarcat@remote-annex","true"]
    [2021-08-19 10:39:06.5226911] process [2036949] done ExitFailure 1

### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)

I'm a long time git-annex user (early adopter, even?) and git-annex is generally serving my uses very well, both as a backup and archival system. The encryption features, however, are a bit more obscure than my tolerance level right now. Thankfully, there is the [[special_remotes/borg/]] I'm thinking of using to replace all this complexity in the future... 

-- [[done]], problem was with a configuration in the gcrypt remote sandbox. -- [[anarcat]]
